Jar mill



Dec. 23, 1941. T. A. HlBBlNs JAR MILL Filed oct'r, 1958 S .m mw 1P 4 5] 5 m s 1 J 6 30 5 Z a 4 r 12.1 m ,M M i M T a U my; mlvv? .2

Patented Dec. 23, 1941 JAR MILL Thomas A. Hibbins, Wellsville, Ohio, assigner to The Stevenson Company, Wellsville, Ohio, a

corporation of Ohio Application October 7, 1938, Serial No. 233,795

(Cl. 21S- 88) 2 Claims.

IThis invention relates to mills for the pulverizing and mixing of materials and to that type of mill which is known as a jar mill and particularly to a jar for such mills.

Mills of this character comprise a jar `usually made of porcelain or earthenware but also commonly made of glass or steel. The material to be treated is placed in the jar along with heavy balls or pebbles and the jar is then rotated until the material has been pulverized or mixed, as desired.

The jars for mills of this general character, as heretofore most commonly constructed comprise an earthenware or porcelain jar having a body with a neck portion at the top. 'Ihe neck portion is outwardly iiared. A metal band circles the jar at the base of the neck and serves to provide means for holding the cover onto the jar. The neck of the jar is commonly notched at diametrically opposite points to receive a cross bar, which cross bar in turn has a screw for holding the cover in the top of the jar. The jars are rotated by being placed in a chuck or a clamp which is mounted on a rotatable spindle. To remove the jar from the mill the mill must be stopped and the jar released from the clamp or the chuck. In other types of mills, the jars are placed on spaced parallel rollers, one of which is driven, and the jar rotated by reason of its being supported on the rollers.

One difficulty with jars as heretofore constructed has been the fact that they are very likely to be broken through the compression of the clamping ring about the flared neck or by reason of some impact against the neck. Another disadvantage is that such jars, especially in the smaller sizes, had the cover holding means projecting beyond the diameter of the jar so that the jar could not be set on driving rollers Without the use of rings placed about the jars to engage the rollers and give clearance for the cover holding means.

The present invention provides a jar especially constructed for use on rollers but is also adaptable for use in the more common types of jar mills having chucks or clamps for holding the jar, the jar being stronger and less subject to breakage around the neck than jars heretofore provided. 'I'he invention further provides an improved clamping for securing the cover to the jar.

My invention will be readily understood by reference to the accompanying drawing which illustrate certain embodiments of the invention and in which Figure 1 is a top plan view of a jar embodying my invention;

Figure 2 is a side elevation thereof;

Figure 3 is a transverse vertical section through the jar on substantially the plane of line III-III of Figure 1, the view being on a somewhat larger scale than Figure 1;

Figure 4 is a detail view showing a side elevation of the clamping collar detached from the jar.

Referring to the drawing, the jar designated generally at 2 has a main body portion 3 with cylindrical sides and a bottom 4. The exterior of the body of the jar has a shoulder 5 above which projects a neck 6, the exterior of which is substantially cylindrical or straight sided. The neck is provided at intervals around its periphery with hemispherical indentations 'I. The inside of the neck of the jar slopes inwardly to an annular lip or ledge 8 so that the neck of the jar is of inwardly or downwardly increasing thickness. The top of the ledge 8 is above theshoulder, and the interior of the jar slopes upwardly, as indicated at 9,toward this lip or ledge. The jar may be formed of any of the materials commonly used for this purpose, porcelain being the most generally employed.

Around the outside of the neck is a metal clamping collar comprised of two similar parts Il] bolted together at II. This collar is formed with projections I2 on its inner surface which fit into the indentations 'I. in the neck. At diametrically opposite points the collar is provided with upwardly extending lugs I3 having overhanging hooks I4. These hooks, best shown in Figure 4, have a slightly downwardly turned terminal or tip portion I5. On the edge of the band under the hooks are flat projections Ma which taper oif into the rim or iiange, the inclined surface at the free end of the lug being designated Ilib. These hooks are adapted to engage the ends of a crossbar I6, which cross bar has a threaded opening at the center thereof. Passing through the threaded opening is a threaded bushing I1 having a hand wheel I8 at its upper end. Within the bushing II is a pin I9. The pin I9 projects below the bushing and is non-rotatably imbedded at 20 in a cover 2|. The lower end of the bushing bears against a washer 22 on the top of the cover. The cover is preferably made of the same material as the body of the jar. It has a central portion which iits inside the lip of the jar and a projecting ange portion 2Ia that overhangs the'lip. A gasket 23 is interpositioned between the lip and the ange 2Ia.

The diameter of the neck and the diameter of the collar around the neck are such that no portion of the collar projects beyond the body 3 of the jar. The jar has a maximum Wall thickness at the point where the neck merges into the body of the jar. The jar is thus strongest at the point where jars as heretofore constructed have exhibited a tendency to break. The wide metal collar encircling the cylindricalneck reinforces the neck and protects it from impact against rigid objects. The interfitting projections and recesses on the collar and neck hold the collar from rotating on the neck and also hold the collar from sliding off endwise of the neck. The clamping pressure of the collar is distributed over a wide area and the use of an exteriorly flared neck to resist endwise movement is unnecessary.

The arrangement for holding and clamping the cover is of considerable advantage. The cover holding bar I6 and the cover are connected `together at all times so that they can be handled as a single unit. When the cover is being put onto the jar, the cross bar is set at an angle where it is clear of the hooks Ill. When the cover is centered, the cross bar I6 is turned so as to come under the hooks. In being turned it rides up thevinclined surface Mb onto the projections or lugs Ella. When the cross bar rests on these lugs, it is elevated above the end of the jar so that if the jar is made of frangible material it cannot exert any pressure likely to fracture the edge of the jar. Also, this movement of the cross bar up onto-the lugs reduces the extent to which the hand wheel must be turned in applying and removing the cover. Since the collar l is restrained against rotative movement on the neck of the jar, it is unnecessary to have any notches in the neck of the jar to receive the cross bar as has heretofore been common in devices of this kind. When the hand wheel is turned in a direction to tighten the cover, the cross bar I6 is thrust upwardly against the underside of the hooks lll and the dependingtips l5 prevent angular displacement of the bar after the cover has been tightened down. When the hand wheel is turned to loosen the cover, cross bar I6 moves down to engage the tops of the lugs 14a. llt not infrequently happens that the cover or door sticks either due to the pressure or due to the fact that sometimes' in grinding material a vacuum develops in the jar. When the cross bar I6 is resting on the lugs M, the hand wheel can be turned to break the seal or vacuum which is holding the cover in tightly and thereby facilitate the removal of the cover. When the cover is loose, the cross bar I6 can be turned to a position where it is clear of the hooks and the cover and cross bar may be removed as a unit.

By forming the cover 2l with a central portion which projects into the opening in the top of the jar and a flange 21a which overhangs the flange 8 of the jar, the cover automatically centers itself. The gasket is effective to seal the cover against loss of material and the part of the cover Which projects into the neck opening eliminates the pocket which would form if the lid were made flat as they usually are.

The jar may be conveniently used in any standard jar mill frame or it may be used on any type of rotating means on which parallel supporting rollers are employed because none of the parts for holding the cover in place project beyond the over-al1 diameter of the jar itself.

While I have illustrated and described certain particular embodiments of my invention, it will be understood that various changes andrmodications may be made in the construction within the contemplation of my invention and under the scope of the following claims.

I claim:

l. `A jar adapted to be disposed on spaced supporting rollers forrotation thereon, said jar including a cylindrical body and a reduced neck thereabove, hemispherical recesses spaced circumferentially of said neck, a collar about said neck having rounded projections fitting into said recesses, and hooks extending upwardly from said collar adapted to receive a cover-securing crossbar, said neck, hooks and bar terminating within the projection of the cylindrical body whereby the jar turns smoothly when placed on supportingrollers. v

2. A jar adapted to be disposed on spaced supporting rollers for rotation thereon, said jar including a cylindrical body and a reduced neck thereabove substantially cylindrical on the exterior, the interior of the neck converging inwardly providing the neck with a wall thickness increasing inwardly, an annular lip extending inwardly from the inner portion of the neck and providing reinforcement for the neck, the exn terior of the neck having circumferentially spaced recesses therein, a collar surrounding that portion-of said neck reinforced by said lip and having projections tting into said recesses, a separate'cover-holding bar, and means on said collar within a cylinder through the maximum diameter-portion thereof engaging said bar.

THOMAS A. HIBBINS. 

